public class ThreadJoin implements Runnable {
    Cake cake;
    Thread joinThread;
    public void setJoinThread(Thread t) {
        joinThread=t;
    }
    public void run() {
        if(Thread.currentThread().getName().equals("顾客")) {
            System.out.println(Thread.currentThread().getName()+"等待"+
                    joinThread.getName()+"制作生日蛋糕");
            try{  joinThread.start();
                joinThread.join();             //当前线程开始等待joinThread结束
            }
            catch(InterruptedException e){}
            System.out.println(Thread.currentThread().getName()+
                    "买了"+cake.name+" 价钱:"+cake.price);
        }
        else if(Thread.currentThread()==joinThread) {
            System.out.println(joinThread.getName()+"开始制作生日蛋糕,请等...");
            try { Thread.sleep(2000);
            }
            catch(InterruptedException e){}
            cake=new Cake("生日蛋糕",158) ;
            System.out.println(joinThread.getName()+"制作完毕");
        }
    }
    class Cake {  //内部类
        int price;
        String name;
        Cake(String name,int price) {
            this.name=name;
            this.price=price;
        }
    }
}
